ABSTRACT
During the 20th century, floods in Italy have killed or injured more than 4750 people in at least 916 fatal flood events, at 739 different sites. This chapter investigates the temporal and the geographical variations of flood risk in Italy, and discusses the national flood risk levels to the levels of risk posed by other natural hazards, including landslides, earthquakes and volcanic activity. Individual risk levels are measured by mortality rates, which are given by the number of fatalities in a population, scaled to the size of the population, per unit time. Societal flood risk depends on the relative proportion of small, medium, and large severity events, which control the slope of the Zipf distribution, and on the temporal frequency of the events, i.e. on the number of events in a period, or per unit time. The chapter provides the rationale for establishing insurance against different natural hazards, and for designing national and regional flood risk reduction strategies.
